A Donald Trump presidency would be a "threat to animals everywhere," warned the political arm of the Humane Society, which on Wednesday announced its endorsement of Hillary Clinton with the launch of a new ad campaign that highlights the Republican nominee's abysmal record on animal protection.

"When you consider the potential for advancing animal welfare reforms at the federal level, or rolling back the recent gains and rulemaking actions, there could not be a greater contrast among the White House hopefuls," wrote Humane Society Legislative Fund (HSLF) president Michael Markarian in a blog post.

"One ticket has a clear, compelling record of support for animal protection, while the other has assembled a team of advisors and financial supporters tied in with trophy hunting, puppy mills, factory farming, horse slaughter, and other abusive industries," he continued. "The names that Trump's campaign has floated for engagement on Interior and Agriculture department issues are a 'who's who' of zealous anti-animal welfare activists."

The new ad showcases photographs of Trump's sons, Donald Jr. and Eric, hunting exotic animals and rare species, as well as a number of his agricultural advisors, which include "several active opponents of animal protection policies," the Washington Post recently reported.

The new campaign also features Iowa factory farmer Bruce Rastetter, reportedly the top contender for Trump's Agriculture Secretary. According to the Post's Kathleen Parker, Rastetter's brother "is the chief executive of a company that builds large-scale hog facilities as well as gestation crates for breeding sows."

Markarian continues:

Other agriculture advisors to Trump include: Iowa Gov. Terry Branstad and former Nebraska Gov. Dave Heineman, both of whom signed onto the federal lawsuit to invalidate California’s law restricting the sale of eggs from barren battery cages; former Iowa state Rep. Annette Sweeney, who along with Branstad ushered the nation’s first “ag-gag” bill into law to punish whistleblowers and shield agribusiness from public scrutiny; Texas state agriculture commissioner Sid Miller, who called Meatless Mondays “treasonous”; Oklahoma state Sen. Eddie Fields, author of the bill overturning the state’s 50-year ban on horse slaughter for human consumption; Oklahoma Gov. Mary Fallin, who signed that horse slaughter bill into law; and Missouri state Sen. Brian Munzlinger, who sponsored bills to weaken the voter-approved standards for puppy mills and deregulate canned hunts.

"Trump is surrounding himself with the leading anti-animal advocates in the United States, and at this stage, it appears many of them will not only have a front row seat in the Trump administration, but they'll be at the steering wheel as a Trump administration examines food and agriculture and wildlife policy issues," he warned.

Markarian notes that his organization "supports lawmakers and candidates from all over the political spectrum," evaluating candidates based on a single criterion: "their support for animal protection."

Alternately, he said that the Democratic nominee "has a strong record of taking a stand against many of these issues," pointing to the Clinton campaign's statement on animal welfare as well as her perfect score on the Humane Scorecard during her time as senator in the 108th and 109th Congress. (In 2009, Clinton only scored an 83, partly because she did not co-sponsor a bill which prohibits research on dog and cats "obtained through random sources.)

Finally, Markarian points out, "If elected, Trump would be the first president since Harry Truman without a pet in the White House."